1. Field of the Invention
This invention relates to a transportable antenna for a mobile earth telecommunications station, enabling notably the transmission and reception of images, sound and data with a telecommunications satellite. In particular, it is used for distant coverages in order to retransmit television images and to exchange telephone communications with a television control center in the home country.
2. State of the Prior Art
Currently, the known mobile antennae, given their form and their ground stabilizing equipment, never weigh less than two tons and are not sufficiently dismountable for fast and inexpensive transport by aircraft to the site of intervention. Moreover, the same is true of the electronic equipment associated with the antenna, said equipment being confined in a large technical protection shelter of which the bulkiness and weight are handicaps.
Furthermore, the weight and bulkiness of the equipment and the antenna contributed, by the cost involved, in preventing the conducting of long-distance coverage with images and sound. The users of such antennae, the foremost of which are television channels and private clients, have always considered such coverage to be impossible.
It should be stressed that the main drawback of these known antennae is the fact that they are not dismountable into relatively small parts enabling them to be grouped into parcels that can be easily transported in the holds of long-distance airliners. In fact, the reflector and the frame, which are of the irregular tubular lattice type, are not completely separable from one another. The reflector-frame assembly can be dismounted into a few reflector-frame parts that are of various non-standard forms and of great volume. The dimensions of these parts exceed the maximum length, width and height of 3.07 m, 1.8 m and 1.6 m for packages in the, holds of long-distance airliners. Under these conditions, these known antennae are transported by air in planes called cargos which are specially chartered and whose schedules are highly irregular. This entails a much longer unoperational period for the equipment and antenna than that required time for the separate transportation of the reporting team. In certain cases, the equipment and antenna cannot even be routed by small plane or helicopter to the exact location of direct coverage.
Furthermore, existing and dismountable antennae, which are already too heavy, have are latively small diameter and therefore insufficient radio electrical performances. The hyper frequency source of the antenna must provide a very high output at transmission to achieve the quality objectives required for retransmission of the coverage. In turn, this high output weighs heavily on the transportability qualities of the equipment and antenna as well as on the cost of routing and human services insofar as higher hyper frequency source power requires heavier electronic equipment. In particular, the equipment requires a power supply of very high output, thereby increasing the bulkiness and the weight of the assembly.